focus stacking

Sometimes, less is more. Sometimes, more is more. There is a type of person who believes that if enough photos of the same subject are taken, one of them will shine above the rest as a gleaming example of what is possible with a phone camera and a steady hand. Other people know how to frame a picture before hitting the shutter button. In some cases, the best method may be snapping a handful of photos to get one good one, not by chance, but by design.

[The Thought Emporium]’s video, also below the break, is about getting crisp pictures from a DSLR camera and a microscope using focus stacking, sometimes called image stacking. The premise is to take a series of photos that each have a different part of the subject in focus. In a microscope, this range will be microscopic but in a park, that could be several meters. When the images are combined, he uses Adobe products, the areas in focus are saved while the out-of-focus areas are discarded and the result is a single photo with an impossible depth of focus. We can’t help but remember those light-field cameras which didn’t rely on moving lenses to focus but took many photos, each at a different focal range.

Focus stacking makes for fantastic macro images, but the process can be tedious without the right tools. While some focus stacking rigs require the camera to be moved away from the subject in small increments, others choose to keep the camera stationary while focusing the lens before each shot.

Both methods produce great results, but you need a steady hand and a lot of patience to get the job done. [Oleg] uses the focus stacking technique relatively frequently, so he decided to automate the process in order to save himself some time. Using an Arduino and a USB host shield from Adafruit, he put together a focus stacking assistant for his Canon EOS camera.

The assistant allows him to set two focal points, leaving the Arduino and his camera with the task of taking pictures. The Arduino commands the camera to tweak the focal point ever so slightly between each image, resulting in an array of images ready for stacking.

He says that the process is a bit slow at the moment, but he’ll be cleaning up the code and building a Nikon-compatible unit in the weeks to come.